<?xml version="1.0" encoding="UTF-8" standalone="no"?>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
  <head>
    <meta http-equiv="Content-Type" content="text/html; charset=UTF-8" />
    <title>Creating Tuple-Serial Entity Bindings</title>
    <link rel="stylesheet" href="gettingStarted.css" type="text/css" />
    <meta name="generator" content="DocBook XSL Stylesheets V1.73.2" />
    <link rel="start" href="index.html" title="Berkeley DB Java Edition Collections Tutorial" />
    <link rel="up" href="Tuple.html" title="Chapter 5.  Using Tuples" />
    <link rel="prev" href="tuplekeybindings.html" title="Creating Tuple Key Bindings" />
    <link rel="next" href="sortedcollections.html" title="Using Sorted Collections" />
  </head>
  <body>
    <div class="navheader">
      <table width="100%" summary="Navigation header">
        <tr>
          <th colspan="3" align="center">
Creating Tuple-Serial Entity Bindings
</th>
        </tr>
        <tr>
          <td width="20%" align="left"><a accesskey="p" href="tuplekeybindings.html">Prev</a> </td>
          <th width="60%" align="center">Chapter 5. 
		Using Tuples
	</th>
          <td width="20%" align="right"> <a accesskey="n" href="sortedcollections.html">Next</a></td>
        </tr>
      </table>
      <hr />
    </div>
    <div class="sect1" lang="en" xml:lang="en">
      <div class="titlepage">
        <div>
          <div>
            <h2 class="title" style="clear: both"><a id="tuple-serialentitybindings"></a>
Creating Tuple-Serial Entity Bindings
</h2>
          </div>
        </div>
      </div>
      <p>
In the prior example serial keys and serial values were used,
and the 
<a class="ulink" href="../../java/com/sleepycat/bind/serial/SerialSerialBinding.html" target="_top">SerialSerialBinding</a>

base class was used for entity bindings. In this example, tuple
keys and serial values are used and therefore the 
<a class="ulink" href="../../java/com/sleepycat/bind/serial/TupleSerialBinding.html" target="_top">TupleSerialBinding</a>

base class is used for entity bindings.
</p>
      <p>
As with any entity binding, a key and value is converted to an
entity in the 
<a class="ulink" href="../../java/com/sleepycat/bind/serial/TupleSerialBinding.html#entryToObject(com.sleepycat.bind.tuple.TupleInput,%20java.lang.Object)" target="_top">TupleSerialBinding.entryToObject</a>

method, and from an entity to
a key and value in the 
<a class="ulink" href="../../java/com/sleepycat/bind/serial/TupleSerialBinding.html#objectToKey(java.lang.Object,%20com.sleepycat.db.DatabaseEntry)" target="_top">TupleSerialBinding.objectToKey</a>

and 
<a class="ulink" href="../../java/com/sleepycat/bind/serial/TupleSerialBinding.html#objectToData(java.lang.Object)" target="_top">TupleSerialBinding.objectToData</a>

methods. But since keys are
stored as tuples, not as serialized objects, key fields are read
and written using the 
<a class="ulink" href="../../java/com/sleepycat/bind/tuple/TupleInput.html" target="_top">TupleInput</a>

and 
<a class="ulink" href="../../java/com/sleepycat/bind/tuple/TupleOutput.html" target="_top">TupleOutput</a>

parameters.
</p>
      <p>
The <code class="classname">SampleViews</code> class contains the modified entity
binding classes that were defined in the prior example:
<code class="classname">PartBinding</code>, <code class="classname">SupplierBinding</code> and
<code class="classname">ShipmentBinding</code>.
</p>
      <a id="tuple_partbinding"></a>
      <pre class="programlisting"><strong class="userinput"><code>import com.sleepycat.bind.serial.TupleSerialBinding;
import com.sleepycat.bind.tuple.TupleInput;
import com.sleepycat.bind.tuple.TupleOutput;
...</code></strong>
public class SampleViews
{
    ...
    private static class PartBinding extends <strong class="userinput"><code>TupleSerialBinding</code></strong> 
    {
        private PartBinding(ClassCatalog classCatalog, <strong class="userinput"><code>Class dataClass</code></strong>)
        {
            super(classCatalog, dataClass);
        }
        public Object entryToObject(<strong class="userinput"><code>TupleInput</code></strong> keyInput, Object dataInput)
        {
<strong class="userinput"><code>            String number = keyInput.readString();</code></strong>
            PartData data = (PartData) dataInput;
            return new Part(<strong class="userinput"><code>number</code></strong>, data.getName(), data.getColor(),
                            data.getWeight(), data.getCity());
        }
        public void objectToKey(Object object, TupleOutput output)
        {
            Part part = (Part) object;
<strong class="userinput"><code>            output.writeString(part.getNumber());</code></strong>
        }
        public Object objectToData(Object object)
        {
            Part part = (Part) object;
            return new PartData(part.getName(), part.getColor(),
                                 part.getWeight(), part.getCity());
        }
    }
    ...
    private static class SupplierBinding extends <strong class="userinput"><code>TupleSerialBinding</code></strong>
    {
        private SupplierBinding(ClassCatalog classCatalog, <strong class="userinput"><code>Class dataClass</code></strong>)
        {
            super(classCatalog, dataClass);
        }
        public Object entryToObject(<strong class="userinput"><code>TupleInput</code></strong> keyInput, Object dataInput)
        {
<strong class="userinput"><code>            String number = keyInput.readString();</code></strong>
            SupplierData data = (SupplierData) dataInput;
            return new Supplier(<strong class="userinput"><code>number</code></strong>, data.getName(),
                                data.getStatus(), data.getCity());
        }
        public void objectToKey(Object object, TupleOutput output)
        {
            Supplier supplier = (Supplier) object;
<strong class="userinput"><code>            output.writeString(supplier.getNumber());</code></strong>
        }
        public Object objectToData(Object object)
        {
            Supplier supplier = (Supplier) object;
            return new SupplierData(supplier.getName(), 
                                    supplier.getStatus(),
                                    supplier.getCity());
        }
    }
    ...
    private static class ShipmentBinding extends <strong class="userinput"><code>TupleSerialBinding</code></strong>
    {
        private ShipmentBinding(ClassCatalog classCatalog, <strong class="userinput"><code>Class dataClass</code></strong>)
        {
            super(classCatalog, dataClass);
        }
        public Object entryToObject(<strong class="userinput"><code>TupleInput</code></strong> keyInput, Object dataInput)
        {
<strong class="userinput"><code>            String partNumber = keyInput.readString();
            String supplierNumber = keyInput.readString();</code></strong>
            ShipmentData data = (ShipmentData) dataInput;
            return new Shipment(<strong class="userinput"><code>partNumber, supplierNumber</code></strong>,
                                data.getQuantity());
        }
        public void objectToKey(Object object, TupleOutput output)
        {
            Shipment shipment = (Shipment) object;
<strong class="userinput"><code>            output.writeString(shipment.getPartNumber());
            output.writeString(shipment.getSupplierNumber());</code></strong>
        }
        public Object objectToData(Object object)
        {
            Shipment shipment = (Shipment) object;
            return new ShipmentData(shipment.getQuantity());
        }
    }
    ...
} </pre>
    </div>
    <div class="navfooter">
      <hr />
      <table width="100%" summary="Navigation footer">
        <tr>
          <td width="40%" align="left"><a accesskey="p" href="tuplekeybindings.html">Prev</a> </td>
          <td width="20%" align="center">
            <a accesskey="u" href="Tuple.html">Up</a>
          </td>
          <td width="40%" align="right"> <a accesskey="n" href="sortedcollections.html">Next</a></td>
        </tr>
        <tr>
          <td width="40%" align="left" valign="top">
		Creating Tuple Key Bindings
	 </td>
          <td width="20%" align="center">
            <a accesskey="h" href="index.html">Home</a>
          </td>
          <td width="40%" align="right" valign="top"> 
		Using Sorted Collections
	</td>
        </tr>
      </table>
    </div>
  </body>
</html>
